Group-wise total in Pandas

Question

I have a pandas table like below with groupby applied to get Groups 0, 1 and 2 as follows:

Group 0	Group 1	Group 2	Count
A	X1	577.5000	6
		894.8700	2
	X2	2697.3100	48
		2697.3100	1
	B3	2697.3100	30
B	C12	34.2700	9
		39.2700	3

I would like to get group wise total in pandas like below:

Group 0	Group 1	Group 2	Count	Group 1 Total by Count
A	X1	577.5000	6	8
		894.8700	2	8
	X2	2697.3100	48	49
		2697.3100	1	49
	B3	2697.3100	30	30
B	C12	34.2700	9	12
		39.2700	3	12

I am able to calculate cumulative sum using df.groupby(level=[0,1]).cumsum() but now sure if there is a way to achieve this.

Answer 1

You can use groupby.transform to transform a sum call over the groups.

df['Group 1 Total by Count'] = df.groupby(['Group 0', 'Group 1'])['Count'].transform('sum')